070_015_Bubbles

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Bubbles

var data = {
labels : ["January","February","March","April","May","June","July"],
datasets : [
    {
        pointColor : "rgba(25,220,220,0.4)",
        pointStrokeColor : "#fff",
        data : [65,59,90,81,56,55,40],
        bubble_data : [13,22,54,37,18,41,53],
        title : "Year 2014"
    },
    {
        pointColor : "rgba(220,220,25,0.4)",
        pointStrokeColor : "#fff",
        data : [28,48,40,19,96,27,100],
        bubble_data : [32,27,51,33,17,31,43],
        title : "Year 2013"
    }
]
}

The data structure for the Bubble chart is very similar to the structure of the Line Chart. In fact, Bubble chart is just a variant of the Line Chart. For Bubble charts, you have to specify the ´bubble_data´ variable which characterise the radius of the bubble.

How is computed the radius of a point ?

The radius is computed according 4 values :

1. The bubble_data value associated to the point;
2. A maximum value (by default, the maximum of all bubble_data values - see option bubbleMaxVal)
3. A minimum value (by default, 0 - see option bubbleMinVal)
4. A proportion value (by default 0.2 - see option bubbleMaxRadius)

The "maximum displayable" radius is computed as the proportion of the minimum between the chart width and the chart height.

Example: if the chart is displayed in an area having a height of 200 pixels and an width of 600 pixels, the minimum between the two is 200. If the proportion is 0.2, the "maximum displayable" radius will be 0.2 x 200 pixels = 40 pixels.

A point with a value equal to the minimum value (3) will have a null radius. A point with a value equal to the maximum value (2) will have the "maximum displayable" radius

See Line structure for additional information.

Bubbles with lines

In Bubbles chart, you can also draw lines.

var data = {
labels : ["January","February","March","April","May","June","July"],
datasets : [
    {
        strokeColor : "black",
        pointColor : "rgba(25,220,220,0.4)",
        pointStrokeColor : "#fff",
        data : [65,59,90,81,56,55,40],
        bubble_data : [13,22,54,37,18,41,53],
        type: "Line",
        title : "Year 2014"
    },
    {
        pointColor : "rgba(220,220,25,0.4)",
        pointStrokeColor : "#fff",
        data : [28,48,40,19,96,27,100],
        bubble_data : [32,27,51,33,17,31,43],
        title : "Year 2013"
    }
]
}

To associate a datasets element to a line, you just have to define 'type : "Line"' in the data.

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